<template>
    <div class="app-container">
        <el-button type="primary" @click="handleAddRole">New Role</el-button>

        <el-table :data="rolesList" style="width: 100%;margin-top:30px;" border>
            <el-table-column align="center" label="Role Key" width="220">
                <template slot-scope="scope">
                    {{ scope.row.key }}
                </template>
            </el-table-column>
            <el-table-column align="center" label="Role Name" width="220">
                <template slot-scope="scope">
                    {{ scope.row.name }}
                </template>
            </el-table-column>
            <el-table-column align="header-center" label="Description">
                <template slot-scope="scope">
                    {{ scope.row.description }}
                </template>
            </el-table-column>
            <el-table-column align="center" label="Operations">
                <template slot-scope="scope">
                    <el-button type="primary" size="small" @click="handleEdit(scope)">Edit</el-button>
                    <el-button type="danger" size="small" @click="handleDelete(scope)">Delete</el-button>
                </template>
            </el-table-column>
        </el-table>

        <el-dialog :visible.sync="dialogVisible" :title="dialogType==='edit'?'Edit Role':'New Role'">
            <el-form :model="role" label-width="80px" label-position="left">
                <el-form-item label="Name">
                    <el-input v-model="role.name" placeholder="Role Name" />
                </el-form-item>
                <el-form-item label="Desc">
                    <el-input
                        v-model="role.description"
                        :autosize="{ minRows: 2, maxRows: 4}"
                        type="textarea"
                        placeholder="Role Description"
                    />
                </el-form-item>
                <el-form-item label="Menus">
                    <el-tree
                        ref="tree"
                        :check-strictly="checkStrictly"
                        :data="routesData"
                        :props="defaultProps"
                        show-checkbox
                        node-key="path"
                        class="permission-tree"
                    />
                </el-form-item>
            </el-form>
            <div style="text-align:right;">
                <el-button type="danger" @click="dialogVisible=false">Cancel</el-button>
                <el-button type="primary" @click="confirmRole">Confirm</el-button>
            </div>
        </el-dialog>
    </div>
</template>

<script>
import path from "path";
import { deepClone } from "@/utils";
import { getRoutes, getRoles, addRole, deleteRole, updateRole } from "@/api/role";

const defaultRole = {
    key: "",
    name: "",
    description: "",
    routes: []
};

export default {
    data() {
        return {
            role: Object.assign({}, defaultRole),
            routes: [],
            rolesList: [],
            dialogVisible: false,
            dialogType: "new",
            checkStrictly: false,
            defaultProps: {
                children: "children",
                label: "title"
            }
        };
    },
    computed: {
        routesData() {
            return this.routes;
        }
    },
    created() {
    // Mock: get all routes and roles list from server
        this.getRoutes();
        this.getRoles();
    },
    methods: {
        async getRoutes() {
            const res = await getRoutes();
            this.serviceRoutes = res.data;
            this.routes = this.generateRoutes(res.data);
        },
        async getRoles() {
            const res = await getRoles();
            this.rolesList = res.data;
        },

        // Reshape the routes structure so that it looks the same as the sidebar
        generateRoutes(routes, basePath = "/") {
            const res = [];

            for (let route of routes) {
                // skip some route
                if (route.hidden) { continue; }

                const onlyOneShowingChild = this.onlyOneShowingChild(route.children, route);

                if (route.children && onlyOneShowingChild && !route.alwaysShow) {
                    route = onlyOneShowingChild;
                }

                const data = {
                    path: path.resolve(basePath, route.path),
                    title: route.meta && route.meta.title

                };

                // recursive child routes
                if (route.children) {
                    data.children = this.generateRoutes(route.children, data.path);
                }
                res.push(data);
            }
            return res;
        },
        generateArr(routes) {
            let data = [];
            routes.forEach(route => {
                data.push(route);
                if (route.children) {
                    const temp = this.generateArr(route.children);
                    if (temp.length > 0) {
                        data = [...data, ...temp];
                    }
                }
            });
            return data;
        },
        handleAddRole() {
            this.role = Object.assign({}, defaultRole);
            if (this.$refs.tree) {
                this.$refs.tree.setCheckedNodes([]);
            }
            this.dialogType = "new";
            this.dialogVisible = true;
        },
        handleEdit(scope) {
            this.dialogType = "edit";
            this.dialogVisible = true;
            this.checkStrictly = true;
            this.role = deepClone(scope.row);
            this.$nextTick(() => {
                const routes = this.generateRoutes(this.role.routes);
                this.$refs.tree.setCheckedNodes(this.generateArr(routes));
                // set checked state of a node not affects its father and child nodes
                this.checkStrictly = false;
            });
        },
        handleDelete({ $index, row }) {
            this.$confirm("Confirm to remove the role?", "Warning", {
                confirmButtonText: "Confirm",
                cancelButtonText: "Cancel",
                type: "warning"
            })
                .then(async() => {
                    await deleteRole(row.key);
                    this.rolesList.splice($index, 1);
                    this.$message({
                        type: "success",
                        message: "Delete succed!"
                    });
                })
                .catch(err => { console.error(err); });
        },
        generateTree(routes, basePath = "/", checkedKeys) {
            const res = [];

            for (const route of routes) {
                const routePath = path.resolve(basePath, route.path);

                // recursive child routes
                if (route.children) {
                    route.children = this.generateTree(route.children, routePath, checkedKeys);
                }

                if (checkedKeys.includes(routePath) || (route.children && route.children.length >= 1)) {
                    res.push(route);
                }
            }
            return res;
        },
        async confirmRole() {
            const isEdit = this.dialogType === "edit";

            const checkedKeys = this.$refs.tree.getCheckedKeys();
            this.role.routes = this.generateTree(deepClone(this.serviceRoutes), "/", checkedKeys);

            if (isEdit) {
                await updateRole(this.role.key, this.role);
                for (let index = 0; index < this.rolesList.length; index++) {
                    if (this.rolesList[index].key === this.role.key) {
                        this.rolesList.splice(index, 1, Object.assign({}, this.role));
                        break;
                    }
                }
            } else {
                const { data } = await addRole(this.role);
                this.role.key = data.key;
                this.rolesList.push(this.role);
            }

            const { description, key, name } = this.role;
            this.dialogVisible = false;
            this.$notify({
                title: "Success",
                dangerouslyUseHTMLString: true,
                message: `
            <div>Role Key: ${key}</div>
            <div>Role Name: ${name}</div>
            <div>Description: ${description}</div>
          `,
                type: "success"
            });
        },
        // reference: src/view/layout/components/Sidebar/SidebarItem.vue
        onlyOneShowingChild(children = [], parent) {
            let onlyOneChild = null;
            const showingChildren = children.filter(item => !item.hidden);

            // When there is only one child route, the child route is displayed by default
            if (showingChildren.length === 1) {
                onlyOneChild = showingChildren[0];
                onlyOneChild.path = path.resolve(parent.path, onlyOneChild.path);
                return onlyOneChild;
            }

            // Show parent if there are no child route to display
            if (showingChildren.length === 0) {
                onlyOneChild = { ... parent, path: "", noShowingChildren: true };
                return onlyOneChild;
            }

            return false;
        }
    }
};
</script>

<style lang="scss" scoped>
.app-container {
  .roles-table {
    margin-top: 30px;
  }
  .permission-tree {
    margin-bottom: 30px;
  }
}
</style>
